There is considerable interest in developing distributed information systems on top of legacy systems. Over the last two decades, many issues and solutions have been brought forward pertaining to issues of integration, e.g., schema integration, schema mapping. We have developed a schema mapping framework that features domain-specific metamodels, metamodel-driven schema translation, and semi-automated schema mapping driven by the metamodel. First, we exploit metamodels, i.e., models about models, which transcend heterogeneity among different data models. Second, we enhance them with domain semantics to better express metadata, resulting in less ambiguous information schemas. Third, we develop our own methods of schema translation and schema mapping based on the domain-specific metamodel, capable of a significant degree of semi-automation for convenience and adherence to the metamodel. Finally, our metadata management framework uses metadata repositories that facilitate reuse, interoperability and extensibility. This paper describes our implementation and utilization of domain-specific metamodels within the schema mapping framework that we have developed.